A BACK injury has added to Jack Viney's pre-season fitness battles, with the Melbourne leader to be missing for a significant start to the Demons' season.

Viney has been curtailed over summer by an Achilles injury and after stepping up his running, the club in January said it expected him to return to full training in the coming weeks.

However, Viney's load has decreased, with a back issue flaring up in recent times after building his training program, forcing the Demons to take an extra cautious approach with the 31-year-old.

The 2021 premiership midfielder's lack of involvement in training this week highlighted he will be set for a delayed start to the season under new coach Steven King.

Viney has barely trained across this summer, with the 237-game midfielder restricted by the Achilles soreness in December and the back injury now also being managed.

It will mean the Demons will have a much different midfield to open their season against St Kilda in round one, with long-time midfield stars Christian Petracca and Clayton Oliver leaving during last year's Trade Period.

Former Saints skipper Jack Steele will be in the Dees' engine room, with exciting draftees Harvey Langford, Caleb Windsor and Xavier Lindsay all likely to feature, while Kysaiah Pickett showed his brilliance up the ground last year.